Bottom hole choke



Sept 29, 1942 E. L. BARKER :TAL 2,297,044

BoTToMAHoLE cHoKE Filed March-14, 1959 Patented Sept. 29, 1942 A FICE BOTTOM HOLE CHOKE Ernest L. Barker andy Charles P. Gillespie,

Houston, Tex.

Application March 14, 1939, Serial No. 261,732

Claims.

This invention relates to well chokes, and has particular reference to that type of well choke customarily referred to as bottom hole choke.

The general object of this invention is to prou vide a bottom hole choke which may be placed in and removed 'from a well whenever desired without necessity for removing the well tubing.

It is to be understood that the term bottom hole choke wherever used in this application is to be taken as meaning any 'choke which is adapted to be located in a well below the upper end thereof. It is not intended to be limited to a choke located at the extreme bottom end of the well.

Under certain circumstances it has been found desirable to place well chokes at a point down in the well usually near the bottom thereof, rather than to place the choke in the Christmas tree at the top of the well as is perhaps the most common practice. Modern wells, however, are drilled frequently to greater depths, sometimes approaching three miles below the surface of the earth and it is not at all inconceivable that wells in the not distant future will exceed three miles in depth. The expense and time involved in removing and inserting a tubing of such great length is such that` it would be prohibitive to permanently position a choke in the bottom of a tubing of a well of such great depth because this would necessitate the removal and replacement of the entire tubing whenever the choke happened to wear out due to abrasion or become otherwise damaged or plugged. Furthermore.- although various attempts have been made in the past to provide chokes which may be dropped or lowered into \the tubing to seatadjacent the bottom thereof and to be removed therefrom by means of a cable or the like when desired, these have proven objectionable because in many instances they cannot even be made to move downwardly in the well. The choke assemblyris necessarily of a size to substantially fill the tubing and the choke opening is so small that if the well is such as to producel a great volume, the flow from the well may be greater than will move past and through the choke assembly. In such instance, naturally,

the device will be carried upwardly by the flow and not permittedl to move downwardly'into the well. Evenif there be no flow as for example if the well is completely closed down during` the 1time the device is being lowered into the well, substantially the entire amount of iluid in the well must pass through the relatively small choke opening as the devicev passes downward toward move very slowly indeed and in the case of wells' of great depth such as hereinbefore referred to necessitates a long period of shut-down. l

It is one of the objects of this invention to provide a choke which may be quickly lowered into place within ai well through the well tubing orl other flow pipe in the well, and without any connection with the upper end of the well.

Another object is to provideA a means for retrieving such a choke assembly, which means will A ordinarily not require the use of a cable. or the like and will not require the removal of the well tubing.

Another object of this invention is to provide a choke which may be placed in 'or removed from a well without necessity for removing the well tubing and withoutnecessity for shutting downV the well for any considerable period of time.

Other objects and advantages will appear more fully fromthe following description taken in connection with the accompanying drawing, wherein is set forth one embodiment of this invention ,by way of illustration and example.

In the drawing: f

Fig. 1 is a longitudinal cross section through a choke assembly constructed in accordance with this invention, as the same appears when it is about to be lowered into a well.

Fig. 2 is a similar view showing the same device after it has been positioned at the desired point within a well tubing.

Fig. 3 is a view siinilar to Fig. 2 but on a re,- duced scale and illustrating ,the means and'ma'nner of withdrawing or retrieving the choke assembly. l

Fig. 4 is a transverse'cross section taken along the line 4 4 of Fig. 3.

Fig. 5 lis a transverse cross A'section taken along l the line 5-5 of Fig. 1.

Fig. 6 is a transverse cross section taken along the line 6 6 of Fig. 1. Y

Fig. 7 is a' transverse cross section taken along the line 1-1 of Fig. 1. In accordance with this invention, I which consists simply of a tubular member with an opening therethrough of the size which is desired for the choke, is carried by a member 2 forming part of a choke holder. 'Ihe choke l is preferably of very hard material which will resist abrasive and other deteriorating influences existing in an oil'or gas well. The member!` is formed with an enlarged portion orchamber adjacent its upper end and lwith a restricted portion 2a adjacent its lower end. restricted the bottom of the well. This makes the assembly portionZa fits fairly snugly about the choke I.

the choke i Surrounding'the choke I and Vpassing through the part 2a is a plurality of openings 2b which serve Ato yby-pass the'. choke under :certain circumstances as will be presently set forth. 'I'he choke is, at lthe time while 'it is being lowered into'a well, held in the position illustrated in conical seat 6 adapted when the choke memberis moved upwardly within Ythe member 2 to seat within a conical portion I in a second iitting 8. The taper of the surfaces 6 and 1 is such that when these paris are forced together they will stick and the choke I will not thereafter drop away from the member 8.

y The member 8 is threaded into the upper end Stof the member 2 and has a portion immediately abovethe member 2 which is of smaller outer diameter than the member 2. At the upper end of this portion is a shoulder 9 and above this 'shoulder the member 8 isA of the same diameter as the member 2. Between the shoulder 9 and the upper end of the member 2 and surrounding the portion 8 o'f reduced diameter there is a plurality of sealing cups I'Il spaced apart by'space rings Il and turned downwardly so as to expand and form a seal with respect to a well tubing to prevent now upwardly, about the outer portion of the choke holder within which the choke I is mounted.

The upper end of the tting 8 is provided with a portion I2 of enlargera internal diameter and within this portion is carried a part I3 which might be termed a bushing. This part I3Y is bifurcated, and pivoted between the parts thereof at I4 there are levers I5. The upper ends of these levers are of circular or cylindrical form I8 adapted to iit within correspondingly shaped sockets I1 formed in each of a pair of radially movable latching members I8. Each of these latching members has a latching part or bolt which is beveled on its lower outer corner as at I9 and provided with a sharp shoulder at its upperouter corner as shown at 28. Bearing against thelower ends of the levers I and tending to hold them always in a position to move the latching members I8 outwardly, are springs I5a. The lower ends of these levers when the latching members I8 are at their outermost position will li'e closely adjacent to each other and 'y will project inwardly beyond the inner contour of the split bushing I3. The latching members I8 are at their inner ends cut awayas shown at 2l so that when moved to their innermost position they will still leave an opening as great'in diameter as the inner diameter of the bushing I3.

The latching members I8 are carried by a fitting 22 which is secured to the Upper end of the member 8 by means of welding 23 or'tllleA like. .Y

This fitting 22 is preferablyI integral or integrally joined to the upper end of the split bushing I3. This fitting 22 is provided with a portion of reduced external diameter at its upper end, this portion being externally threaded as at 24. The

ntting is also provided with a longitudinal passageway 25 ofthe same diameter as the `split bushing I3,` and this passageway terminates at its upper end with a flared portion 28 so as to guide any member entering the same from above finto the passage 25. f

ing members I8 will be held inwardly by the walls of the tubing 30 and will be permitted to pass by couplings and other obstructions in the tubing -by virtue of the inclined lower outer corners I9. The sealing cups I0 will prevent any flow upwardly around the outside of the assembly but i'iow may take place not only through the interior of the choke I but around the outside of this choke through the by-pass openings 2b. Flow through these openings may pass upwardly through the enlarged interior portion of the member 2 and around the head 5 of the choke, thence upwardly through the member 8, the tting 22 and the fitting2'l, all forming parts of the choke holder. It will thus be seen that substantially free iiow will be permitted upwardly past the choke through the assembly while the same is being lowered into the well. At a point adjacent the lower end of the well`or'wherever it is desired that the choke be positioned. there is inserted in the tubing by any appropriatemeans a spider 3I which forms an abutment for the lower end 4 ofthe choke. This spider 8| in the present instance, as shown in Fig. 2, is located within a collar 32 and between the two adjacent ends of the tubing threaded in said collar. The spider serves as an abutmentl as above stated but has openings 33 therethrough so as to permit substantially free ow of uid from the well. Due to the fact that uid is permitted to by-pass through the passage 2b and is not all forced to flow through the choke I which is of relatively small diameter, the assembly will move quickly to its position within the well and no great amount of time will be required such as would be required if the entire amount of fluid in the well were forced to flow through the choke opening.

When the choke assembly reaches the position where it is to be located in the well, the lower end 4 of the choke will strike the spider 3l causing the shearing of the ends of the screws 3 and the movement of the choke upwardly with respect to the ntting 2. This moves the head 5 upwardly into the lower end of the tting 8 and causes the conical surface 6 to vseat within the portion 'I of the fitting 8. The action just described Will'prevent any further passage of fluid through the openings 2b. The only flow which can now take place from the well past the assembly which has been described is that flow which can take place through the choke I. Inasmuch as the well would force a greater potential output than could pass through the choke I or else the choke would not be needed, pressure will build up underneath the assembly and will tend to move it upwardly in the tubing. This upward movement will take place until the latches I8 arrive at the next coupling 34 above the point where the abutment 3| is reached. When the latches I8 reach the coupling 34 they will be urged outwardly by the springs I5a and will latch well atthis coupling as indicated in Fig. 2. The will now continue to flow through vthe choke I but no other flow can take place. The assembly comprising the fittings 2, 3, 22 and 21 constitute a means for holding this choke and for preventing any passage of fluid around the choke. The sealing cups I forma seal about the outside Vof the choke holder Awhile the choke itself yseats against the portion 1 to prevent the by-passing offluid through the openings 2b.

, In the event thechcke becomes worn so that too great an amount of fluid is allowed rtoflow from the well, or in the event it becomes.A otherbeen provided whereby a choke'rnay be lowered rapidly into a well and removed rapidly therefrom. y 'A All of the objects and advantages sought by this'invention can, it will be appreciated, be accomplished by the structure set forth.

Having described our invention, we claim:

1. In vcombination with a choke adapted to be loweredinto a-we1l to controlflow at a point below the upper end thereof, a choke holder, means on said choke holder. for preventing upflow from n said ,welllalmutsaid.v choke holder, said choke wise damaged or plugged with somev foreign-mat- 1 ter.. provision is made for the withdrawal or retrieving of the choke assembly.

For the purpose of thus withdrawing the choke a weighted body 35 having grooves'36 in its outer surface and having a downwardly projecting porassembly, there is provided a device comprising tion 31 of slightly smaller diameter than the inner diameter of the fitting 21. The weight 35 is preferably of a diameter only slightly smaller A than the inner diameter of the tubing so that' it will serve as a guide for the device whilel the grooves 38 will serve to permit free passage of fluid past the weight as it is lowered into the well. Surrounding the portion 31 which is adapted to enter the fitting 21 there is provided a plurality of sealing'rings38 adapted to contract as they pass into the fitting 21 and to expand within this fitting into the grooves or channels 28.- These will serve to substantially shut off all flow through the choke assembly, whether through the choke proper or otherwise.

At the same time, there is a projection 39 of smaller diameter than the part 31 and of a diameter only slightly smaller than the passage-l way 25. This projection will pass downwardly through the passa e way between the latching members i8 and tween the levers I 5. This part is pointed or tapered on itslower end as shown at 40 so that as it passes between the lower ends of the levers i5 it will force these lower ends away from each other and draw the latching members i8 inwardly out of latching position. This is clearly shown in Fig. 3 of the drawing. The members I8 can move inwardly to unlatched position whenl the member 39 is between them because of the previously described f;

cutaway parts 2| on the inner ends latching members.

It will now be seen that the choke `assembly has been plugged so that substantially no flow can take place from the well past the assembly of these or through it, and it has been unlatched by the the spear head 4| on the upper end of the weight 35.

It will be seen from the foregoing that a means has been provided whereby a choke may be positioned within a well tubing and removed therefrom without necessity for removing the tubing from the well and without necessity for shutting down the well for any considerable period of time. It will further be seen that a means has holder having a passageway for by-passing fluid past s'aid choke through the interior vof said holder while said choke and choke holder are being lowered into a well, means for closing said by-pass passageway when said choke reaches a 2. In a bottom hole choke assembly, a choke,'

a hollow choke holder for holding said choke and having means for by-passing fluid through itself around said choke while the assembly is` being lowered'jnto a Well, means lfor closing said by-'passing means when said choke reaches a predetermined point in the well, meansfor preventin'g upfiow about any portion of said choke holdholder er, and means for latching said choke against upward movement from a well.

3`. In combination a chckeassembly comprising, a choke, a choke holder for holding said choke and having fluid by-pass means for bypassing fluid around said choke while the assembly s being lowered into a well, means for preventing upflow about said-- choke after it has reached a predetermined point'in a well, means for latching said assembly against upward move*- ment from a well, and means for releasing said latching means and shutting oi flow through said choke when it is desired to remove said choke assembly.

4. In combination. a choke, a choke holder lhaving a part of its length provided with a bypass means for conducting fluid around said choke, and part of its length adapted to form a seal about said choke, means for releasably holding said choke in said first part of the choke holder during the lowering of said choke and choke holder intoa well, and means for causing said choke to move into said other part and close ofi said by-pass means when said choke and choke holder reach a predeterminedl point in a well.

5. In combination, a choke, a `choke holder having a part of its length provided with by-pass V`means for conducting fluid around said choke,

and part of. its length adapted to form a seal about said choke, means for releasably holding said -choke ihsaid first part of the choke holder duringthe loweringthereof into a well, means for causing said choke 'to move .into said other part and close off said by-pass means when said choke and choke holder have reached a predetermined point in a well, and means carried by said choke holder for latching the same against upwardmovement in a well.

6. In combination, a choke, a choke holder having a part of its length provided with bypass means for by-passing fluid around said choke and part of itsr length adapted to form a seal about said choke, means for releasably holding said choke in said `first part of the choke holder during the lowering thereof into a well,l

means for causingsaid choke to move into said y other part and close oi! said by-pass means when said choke and choke holder have reached a predetermined point in a well, free oating means for latching said choke holder against upward' movement from a well, and means for releasing said latching means and stopping flow through said choke and choke holder when it is desired to remove said choke from the well.

'7. In combination, a choke, a choke holder havinga lower part provided with by-pass meansfor by-passingyiiuld around said choke and a higher part adapted to form a seal about said\ choke, means for releasably holding said fchoke in said lower part of the choke holder during the lowering thereof into a well, and means for causing said choke to move into said'higher part and close off said by-pass means when said choke and choke holder have reached a predetermined point in the well.

8. In combination, a choke, a choke holder having a lower part provided with iiuid by-pass means for by-passing said choke and an'upper part adapted to form a seal about said choke, frangible means for releasably holding said choke in saidlower part of the choke holder during the lowering thereof into a well, and me'ans for causing said choke to move upwardly into said upper part ofthe' choke holder to close oi said choke assembly, a heavy weighted body having parts adapted to guide the same in its passage through a tubing, said body having parts providing for the passage of uid past the same, a latch releasing part on said body adapted to release said assembly for upward movement in a well, and a part on said body adapted to substantially close said assembly against upii'ow therethrough.

11. In a device for retrieving a bottom hole choke assembly, a heavy weighted body having parts adapted to guide the same in itswpassage through a tubing, said body having parts providing for thepassage of iiuid past the same,

a latch releasing part on said body adapted toA release said assembly forfupward movement in a well, a part on said body adapted to substantially closesaid assembly against upow there through, and means on the upper end of said body adapted vto be engaged by a retrieving tool whereby said body maybe forcibly pulled from la well.

12. In combination, a choke, a choke holder in which said choke is movably mounted, said holder having uid byi-pass means for by-passing iiuid around said choke, means for releasably holding said choke in a position permitting flow through said byJ-passing means while the assembly is being lowered into a well, and means operable when said assembly reaches a Predetermined point in the well for shifting said choke to another position in which it prevents up flow through said by-passing means. 13. In combination, a choke, a choke holder in which said choke is movably mounted, said holder having uid by-pass means for by-passing :duid around said choke, means for releasably holding said choke in a position with its end projecting below said holder while the assembly is being lowered into a well. in which position it permits free flow through said bypassing means, and means engageable with the end of said choke when said assembly reaches a predetermined point in the well for shifting said choke to another position in which it prevents ,up iiow through said by-passing means.

14. In combination, a choke, a choke holder for holding said choke and having iiuid by-pass means for by-passing iluid around said choke while the assembly is being lowered into a well, means operable when said choke reaches a predetermined point in a well for preventing up ow about said choke thereafter, means movable radially through said holder and relatively xed longitudinally thereof for latching said assembly against upward movement from a well, and means separate from but insertable in said holder for releasing said latching means when it is desired to remove said choke assembly from the well.

y 15. In combination, achoke, a choke holder having a part of its length provided with bypass means for conducting iiuid around said choke and part of its length adapted to form a seal about said choke, means for releasably holding said choke in said first part of the vchoke holder during the lowering thereof into a well, means .for causing said choke to move into said other part and close oi said by-pass means when said choke and choke holder have reached a predetermined point in a well, means for latching said choke holder against upward movement from a well, and free iioating means adapted to be dropped into the well for releasing said latching means when it is desiredto remove said choke from a well.

ERNEST L. BARKER. CHARLES P. GILLESPIE. 

